arm: dts: iot2050: Use the auto generator nodes for fdt

Refactor according to the entry `fit: Entry containing a FIT` of
document tools/binman/README.entries.

As the generator uses the device tree name for the config description,
board_fit_config_name_match requires a small adjustment as well.

Signed-off-by: Su Baocheng <baocheng.su@siemens.com>
[Jan: re-add now required CONFIG_OF_LIST, update config matching]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/iot2050_pg2_defconfig b/configs/iot2050_pg2_defconfig
index 58aefac..65400b4 100644
--- a/configs/iot2050_pg2_defconfig
+++ b/configs/iot2050_pg2_defconfig
@@ -71,6 +71,7 @@
 # CONFIG_ISO_PARTITION is not set
 CONFIG_OF_CONTROL=y
 CONFIG_SPL_OF_CONTROL=y
+CONFIG_OF_LIST="k3-am6528-iot2050-basic-pg2 k3-am6548-iot2050-advanced-pg2"
 CONFIG_SPL_MULTI_DTB_FIT=y
 CONFIG_SPL_OF_LIST="k3-am65-iot2050-spl"
 CONFIG_SPL_MULTI_DTB_FIT_NO_COMPRESSION=y